1. Field of the Invention
This invention relates to computer keyboards. More specifically, the present invention relates to remote computer keyboards using either luminescent keys or a lighted keyboard for improved viewing in a dark room.
2. State of the Art
The computer industry has been using remote keyboards for a number of years. Such keyboards typically employ a transmitter, operating within a narrow band of the electromagnetic spectrum, which communicates with a receiver directly coupled to the central processing unit. Signals received from the keyboard are translated into standard keyboard signals understood by the central processing unit. The reason for using a remote keyboard is to remove the necessity of a connection cord between the keyboard and the computer console. A remote keyboard permits the user to submit typed data to the central processing unit anywhere within the range of the transmitter receiver combination. Although infrared band frequencies are generally used from communications between remote computers and central processing units, other frequency bands may also be used successfully. When infrared energy is used for communications between a central processing unit and a remote keyboard, the keyboard must generally remain in the same room and be in a direct line of sight with the infrared receiver. As illustrated in drawing FIG. 1, a typical conventional QWERTY-configured remote keyboard 100 is shown. The keyboard 100 is contained within an enclosure 101 having an portion 101b and a bottom portion 101b. A plurality of key caps 102, which includes keys for space, shift, control and, backspace functions, is surrounded by the upper enclosures 101a. The keyboard 100 also has an infrared transmitter 103 which is coupled to the key caps 102 via an encoder device (not shown). The keyboard 100 is interfaced to a central processing unit 105 via a receiver 104 and decoder device (not shown).
It is readily acknowledged that remote keyboards are generally difficult to use in dark rooms because it is difficult for a computer operator to identify individual keys in the dark. Although most computer users consider themselves typists, such users will typically look at the keyboard when little used keys or key combinations must be pressed. The lack of complete standardization of keyboards exacerbates this problem. Certain multikey combinations, such as Ctrl, Alt, Del, used for a warm boot operation require the operator to remove his hands from the normal typing position. Once the hands are removed, it may be somewhat difficult to return to the normal position and resume touch typing. Thus, it may be concluded that at least the average typist is at a disadvantage in a dark room because he cannot identify individual keys of the keyboard. Although cathode ray tube computer monitors generate sufficient light to illuminate the keyboard at close distances, as the operator distances himself from the monitor, the intensity of illumination drops rapidly.
Computer operators having a remote keyboard have the same problem as an individual attempting to make a telephone call on a telephone with an unlighted keypad. Fortunately, most telephone manufacturers now provide backlighting for telephone keypads so that the numbers are identifiable in the dark. The same may be said for an individual attempting to utilize a television control device in a dimly lit room. Remote control manufacturers for various electronic devices have responded to this problem by providing control keys with identifying markings which fluoresce or luminesce.
Another example of a lighted viewing area is a backlit computer LCD screen which is used, in portable PC computers. Portable LCD computer screens without backlighting are difficult to view under normal lighting conditions, and nearly impossible to view in a dark room. Portable computer manufacturers use backlit computer LCD screens to allow users to see the LCD screens in dark and low light conditions.